


Good Girl

by BlindSwandive



Series: SPN Kink Bingo 2019 fills [1]
Category: Supernatural
Genre: Breeding Kink, Condom fuckery, Dirty Talk, F/M, Gender or Sex Swap, Incest Kink, M/M, Mildly Dubious Consent, Praise Kink, Sex-swap hex, Undernegotiated Kink, girl!Sam
Language: English
Status: Completed
Published: 2019-01-06
Updated: 2019-01-06
Packaged: 2019-10-05 04:17:56
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,912
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/17317949
Author URL: https://archiveofourown.org/users/BlindSwandive/pseuds/BlindSwandive
Summary: Sam and Dean’s little kink for the idea of knocking one another up was always safe to play around with, since there was never any fear it could happen—until Sam got hit by a sex-swap curse.For SPN Kink Bingo 2019, filling the square Impregnation.





	Good Girl

**Author's Note:**

> This is my first time doing a Kink Bingo and I'm kinda having a blast already. Many thanks to [WetSammyWinchester](https://archiveofourown.org/users/wetsammywinchester) for short notice beta!! Feedback is love. <3
> 
> PSA: Please be good and negotiate shit like this ahead of time.

They’d researched how to lift the hex. Of course they had. It just hadn’t done much good. When they called her to consult, Rowena said it would probably wear off naturally, and with no one’s health and wellness in grave danger, she wasn’t particularly interested in spending twelve hours on a bus until they’d given it a week to run its course. If it hadn’t lifted on its own by then, by all means, call her back. In the meantime, try to enjoy it.

Try to enjoy it, she’d said. Sam had been a little miffed by her too-knowing tone, there.

It wasn’t _that_ obvious they were fucking.

\- - -

Later, when they were fucking, they were definitely enjoying it. 

Dean had always bragged of his prowess with cunnilingus, but Sam had more or less dismissed it as false bravado. Dean was generally great in bed, no question, but his blowjobs were average at best. But now that Sam had a—had—well, now that he had different equipment, Dean was showing off and proving himself in no uncertain terms. God, it was like when they’d first broken through the terror and taboo and started fucking—anywhere and everywhere, often enough that they were sacrificing basic needs like food and rest and shelter, full of the wild abandon of young love or lust or whatever it was all over again. Dean had gone down on him three times already that day, just getting this kind of crazed look in his eye out of nowhere and crowding Sam against a wall, pushing him down over a table in the Crow’s Nest, even throwing Sam over his shoulder (he was small enough to do that, now) and hauling him off to bed to suckle his small, high breasts and bite his lean thighs and devour his—his—well, _that_ —like it was manna, the fruit of the gods.

It wasn’t until the second day that Sam started to suspect Dean had an ulterior motive for all of that… devouring. 

Sam was splayed out on the floor in the kitchen, feeling like a pinned butterfly from the way Dean’s forearms were pressing out his thighs, when through all the mind-melting licking and suckling and nibbling there was an uncentered feeling of invasion. It was bizarrely hard to tell (how could it possibly be hard to tell?), but he was pretty sure that Dean was slipping a finger inside of Sam’s new—new _vagina, grow up, Sam, the word wouldn’t bite_ —easing in and probing around. 

It stung on and off, which he couldn’t make sense of through the lust haze, but Dean always seemed to know when he’d made something go ‘wrong’ and would pull his finger back out to plunge his tongue up deep inside, instead. After a few moments, the pain would go down, Dean’s mouth would go back to Sam’s—to Sam’s clit, and once Sam was back to writhing around blissfully, it would start all over again.

Sam was in some kind of confused, delicious agony by the time Dean was scissoring two fingers inside of him. It was so wrong, so… displaced from what he was used to, and he couldn’t understand why it _hurt_ this way, not when women did this every day and seemed to like it. But then Dean would do something indescribable with his tongue and curl his fingers up, and it was just enough like when Dean was sucking Sam’s cock and fingering his ass that he decided he’d trust Dean to do whatever it was he knew how to do and ride it out.

If Dean weren’t such a dedicated hound on his clit, Sam might have been mortified at the squeak that came out of him when Dean stretched him too far, too much at once—and stretching definitely had to be the point of all that scissoring, opening him up and making room—but there wasn’t enough free space left in his brain to worry about it. And anyway, it made Dean let out some kind of dark, delicious sound against him, some thrill at Sam’s abandon or pain or whatever it was, and that tripped something shivering up Sam’s spine.

Even if it hurt Sam or he cried out, Dean wanted to push anyway, and… and Sam thought that shouldn’t turn him on as much as it did, but fuck if he cared about that right now.

When Sam finally came, Dean seemed almost… disappointed? Oh, he helped ease Sam through it, nudging him into aftershocks and slowly back down; he slid his fingers out gently, and licked deep inside of Sam to soothe him; he kissed the inside of one thigh, and the flat plane of Sam’s belly, making Sam jolt when the cooling wetness on Dean’s face chilled his hot skin. And Dean’s mouth, swollen and shiny and red from the work, was quirked up into a satisfied smile. But Sam still had the strangest sense that Dean was stopping under protest, that he wanted _more._

Sam, once his brain came back online, thought that was fair, especially with the sheer glut of orgasms Sam had racked up since the hex, and he lunged up to lick Dean’s chin clean before burying his face in Dean’s cock. It was rigid, hot and weeping even after having been ignored, so at least Sam didn’t have any doubt Dean had been enjoying himself. Sam would happily return the favor.

And, well, if Dean liked eating Sam’s—Sam’s _pussy_ that much, who was Sam to argue?

\- - -

That night, back on the bed like civilized people, Dean was a menace with his fingers. He wriggled two into the hot slick of Sam when they’d barely gotten started, and Sam flailed a fist back into the headboard to keep from making another embarrassing sound. And this time, Dean wasn’t stopping.

Sam tried angling his hips up, even crushing his fingers into Dean’s hair to try to shove his head down, to get him to use that magical tongue to soothe the burn again, but Sam wasn’t quite as strong as an Amazon as he’d been as a sasquatch, to use Dean’s parlance, and Dean was taking every advantage of that. Dean just made some kind of “Nn-nn-nm,” sound, all teasing scolding. Sam punched back into the headboard again.

“C’mon, now,” Dean paused to murmur against him, “be a good girl, Sam.” 

Sam had to clamp a hand over his mouth to keep from moaning outright. He’d never live it down; Dean would never stop bringing it up if he suspected Sam had… had _feelings_ about hearing that, and it would be bad enough if the pang that shot between his legs was somehow detectable to Dean without crying out and making it glaringly obvious. It was mortifying enough to feel it himself without having to hear about it for the next month or year.

But Dean’s fingers didn’t seem to hurt so much, after that, everything down there going sort of hot and liquid. Something in that delicious, burning embarrassment turned some kind of key, maybe, cracking open the lock, and Sam wanted to try. Wanted to try to be a good girl for Dean.

And Dean _did_ notice, the evil fucker. He groaned against Sam’s clit, nosed deeply in the soft curls above, and breathed out a satisfied sigh. “Good girl,” he repeated, just above a whisper. “That’s my good girl.”

Sam bit his own hand but the little high-pitched sound squeaked out anyway, muffled but there. Dean twisted his fingers in some perfect, wicked way and it happened again, soft but undeniable.

Ah, fuck it. Sam threw his arm out and gripped the sheets, instead, wrapping one leg tight over Dean’s shoulder, trying to crush him closer, keening out a strained, “Fuck, Dean…”

Dean’s air all rushed out of him and he started to lift up and off. “Thought you’d never ask,” he breathed, and then he was standing and what clothing he still had on was being shed, fast and violent. Dean fumbled in the nightstand with one hand while he tore a sock off with the other.

Sam’s head was spinning. What? Ask what? He reached toward Dean, trying blindly to bring him back closer, get him back where Sam needed him.

“Hold on, Sammy, gimme a sec,” Dean said, voice low and raw, but then the bed was shifting and he was back between Sam’s thighs, again, naked and kneeling up close. He was stroking his dick, now gleaming with the unnatural shine of lube. 

Sam wrapped his long legs around Dean’s waist, pulling wantonly, trying to tip Dean down against his body. Dean went easily, falling onto his knees and elbows over Sam, and sank until their bellies were flush, face hovering over Sam’s. Sam licked at Dean’s glossy chin shamelessly, as much to try to shock Dean back into motion as for his own satisfaction. (Dean wasn’t the only one who liked the taste of pussy, after all.) But then the tip of Dean’s dick was nudging at him _there,_ feeling impossibly hard and dangerous, and he froze.

A pulse of terror ran through him and Sam started to formulate a protest, tried to come up with the words, but Dean just nuzzled close to his ear and said, “Shh… Thought you were gonna be my good girl?”

And Sam’s hips rocked up at him—all on their own, he’d swear to it—and he fell silent. Just like that.

Sam wondered what the fuck was wrong with him, but Dean nipped at his earlobe and the spot on his neck just below it, and Sam found he didn’t care all that much after all. He nodded, just slightly, and shut his eyes tight, balling his hands tight into the sheets again to brace himself.

Dean laughed soft, half breathless, and mouthed over Sam’s brow where it was knotted. “Relax. Not gonna hurt you.” 

One of Dean’s hands wedged down in between them, and then the head was moving in slow circles over the hood of Sam’s clit, slick and silken. Some of the tension bled out of him, chased by that hot and wanting feeling, and Dean traced the tip up and down along his slit a few times. Gentling him. Getting him used to the threat of it.

Teasing him.

“Do it already,” Sam snapped when it had gone on too long and he was starting to clench on nothing. He kicked one heel down into the meat of Dean’s ass to make his point.

That might not have been his best move, because Dean jolted up inside of him halfway, all at once. Sam wailed, but by the time Dean was shushing him and kissing apologies into his neck, he couldn’t really remember why. He panted to catch his breath, while Dean held impossibly still, and when he was ready, again, he nudged Dean with his ankle, shifting awkwardly to try to make space in this strange body.

Dean slid home slow and easy. Sam was sure now in retrospect that this had been Dean’s plan all along, going down on him over and over and breaking him open on Dean’s fingers so he could get away with this, but he didn’t have it in him to resent the manipulation. It ached a little, even with the lube, even with the seemingly endless supply of fluid Sam was producing, but it was strange and new and delicious, too, wrong and perfect.

Dean let out a wrecked sound against Sam’s neck and rolled his hips, before falling still again and panting.

Sam experimentally tried to get a hold of the muscles there—they were taking a lot of getting used to—and managed to squeeze them, once, briefly, on purpose. There was a jagged breath against his jaw so he tried it again, and felt a little triumphant flutter in his belly when Dean choked.

Unwilling to let Sam get the better of him, apparently, Dean jabbed his hips up sharply, and Sam’s voice betrayed him, letting out a sound that was downright whiny. It hurt, but… it also seemed to touch something too deep inside, too central, like… like maybe his…

Sam felt his skin flush hot, all over his body, and he tried to push the thought away, but once it crept in— _womb_ —it wouldn’t budge. It got in his brain like itching, like buzzing, and he started to squirm, trying to nudge away at Dean.

It was one thing to brush up against the idea when he didn’t _have_ one—frankly, most days, all Dean had to do was mutter something about breeding in his ear and Sam would fold over the nearest flat surface, hot as fire—but _with_ one, the flare of fear was sudden and overwhelming.

“Dean— _Dean,_ ” he insisted, punching him on the shoulder to catch his attention. “Condom!”

Dean didn't let him get any distance, staying determinedly inside. “Why?”

“Because I have a uterus right now, you idiot,” he hissed, rolling to try to buck Dean off and to be able to reach for the nightstand drawer. They hadn’t used condoms in a year or two—not since they’d made their drunken pact to be exclusive and gotten clean blood screens back—but he was sure there’d be one or two left in the drawer. Even expired was better than nothing.

Dean let Sam get loose and over onto his belly, even let him get his hand into the drawer and close his fingers over one of the foil squares, but then two hard hands were braced on his hips and pulling, Dean dragging Sam back along the bed and wedging in between his thighs.

“Dean—” Sam squeaked, swinging a hand back at him, sort of trying to hit him and sort of trying to get him to just take the condom. “Dean, I’m serious—”

Dean’s hand closed on his, pulling the condom from his fingers. Sam tried to crane his neck back to make sure he was actually going to use it, but the angle was bad, and anyway, he heard the foil tear, so his hackles went down and he relaxed into the bed. 

His heart was still jackhammering in his chest, though; he hadn’t realized quite how panicked he was.

And he wasn’t quite sure why he felt a little pang of disappointment, either.

Dean gripped his hips and hauled him up from the bed, rough, until Sam was up on his knees with his breasts and his outstretched arms pressed down into the bed. And then Dean was lining up, nudging Sam’s knees a little further apart to get him back down to the right height (he was slightly taller than Sam, now, but Sam’s legs were still longer) and sank back inside. He felt—God, it felt like he was in deeper now, somehow.

When Sam started to push up onto his elbows, to get a little leverage, Dean flattened a hand into the center of his back, pressing him back down. Sam turned his face into the mattress, because he felt his cheeks going pink; he didn’t need to let Dean see his hot, guilty flush at being held down.

Dean rolled his hips slow, and when Sam curled his fingers down into the sheets and groaned, any struggle forgotten, he let his hands wander reverently. He stroked over Sam’s ribs and hips, down his thighs, dipped his thumbs into the small of Sam’s back.

“Wonder… wonder what would happen if I did knock you up?” Dean rumbled behind him, and one of those disconcerting pangs shot through Sam’s belly again. “If it would just disappear when the spell wore off, or… or if you’d be stuck this way...” His fingers were curling around Sam’s waist, slipping down over his belly. Where—where he’d be swollen and full if he did get pregnant somehow. Sam bit his lip against a moan, but Dean’s next thrust punched it out of him anyway.

“Don’t—don’t even joke about that,” Sam managed to insist, but it didn’t sound like he meant it, not even to his own ears. “I’d murder you in your sleep,” he added, anyway, and Dean let out a thin laugh, sliding his hands along to Sam’s shoulders and then down his arms, bowing over him. He pinned Sam’s wrists under his hands and Sam jerked beneath him.

There was a knot, tight and low in his belly. It wasn’t quite like the feeling he’d gotten when Dean had eaten him to orgasm and it wasn’t like when Dean was riding his prostate, either, not quite centered in the same place, but it was hot and it ached. And when Dean murmured, “You sure?” it pulsed, dangerous and consuming.

Dean nuzzled against Sam’s ear and asked, soft as Sam had ever heard him, “You trust me?”

Sam didn’t even pause to consider. Even the required brotherly retorts died on his tongue, too raw inside. “Yes,” he whispered, “yes.”

Dean nipped his earlobe and rumbled, “Good girl,” again, and the jolt of lust almost hurt. Sam didn’t bother stifling his cry, that time. Dean gathered both of Sam’s hands up, shaking them gently loose from their death grip on the sheets, and shifted back upright to his knees so he could cross Sam’s wrists over the small of his back, pinning them under his grip.

Sam waited for the other shoe to drop—waited for whatever line-crossing was coming if Dean needed to know Sam would trust him—but Dean just held him there and went back to lazily rolling his hips, easy and slow. Sam felt the prickling tension of it start to ease, and a little warily, let himself settle in and just enjoy losing his brand new virginity, enjoy being small enough to wrestle down and trap, enjoy that firm, steady grip on his wrists and Dean’s dick rearranging his insides.

He didn’t think he was going to come this way, but he was sure as hell enjoying himself.

And then Dean said, “Never thought I’d get to breed my baby sister’s pussy.”

Sam was honestly surprised he didn’t just spontaneously die. He was pretty sure he’d just been stabbed, deep and low in his belly, and the end was coming. How could Dean even speak right now, let alone to say something like that? How was he forming coherent sentences?

“Condom,” Sam managed to force out, meaning something like, “Well, that’s nice, but you’re still not going to get the chance because you’re wearing that condom I gave you,” and maybe, “You’d better fucking well be wearing that condom I gave you.” He trusted Dean to understand.

“You actually see me put it on?” Dean asked, low, so low, and that tight knot in Sam’s belly flared, hot and painful, spreading so deep that it felt like it was throbbing around Dean’s dick. He wrenched to try to get his wrists free, feeling half sick and terrified, but Dean squeezed his wrists and shushed him, murmuring soothing nothings, all “Shh, be a good girl for me,” and “Trust me, Sammy.”

Sam’s eyes were wet and blurring, but he tried desperately to shift, to crane his neck to see if he could get a look at the condom wrapper, to see if it was empty or not. He blinked his eyes clear, and had just made out the torn edge, when Dean caught on, letting one hand off of his wrists and swiping the wrapper out of sight, off onto the floor.

“Uh-uh, Sammy,” he panted, grappling to get Sam’s wrists pinned again while he thrashed. “Thought you said you trusted me?”

And Sam did. He really did. Most of the time. And probably… probably Dean was just screwing with him, and probably there’d be no reason to hide the wrapper unless it really was empty and would break the illusion, and probably Dean would know better than to really risk it, but… but…

“Could—could be expired anyway,” Sam whispered, brave and mortified at once.

Dean jolted into him, choking back a moan.

Yeah. Dean wouldn’t really fuck around with something like that. But God, if he _did_ …

Sam didn’t realize he’d fallen still until Dean loosened up on his wrists and let out a shaky, satisfied sigh, one hand stroking up and down one of Sam’s arms. “S’my good girl,” he said, with a tenderness usually reserved for the Impala, “my sweet girl… Fill you up inside, every chance I get ’til this thing wears off…”

Dean’s thrusts were getting erratic, rough and uneven and short, and Sam knew it wasn’t happening, he _knew,_ but he was still so certain Dean must be pushing all the way up inside, right through his cervix and into his womb, must be about to seed him and breed him and mark him for all the world to see… Otherwise, what was that ball of molten heat, that pulsing, delicious ache swelling inside of him there?

There was a bloom of pain through Sam’s shoulders as his wrists were loosed and his arms fell down slack at his sides. Sam would have stayed right there, limp as a ragdoll, but Dean pulled him up bodily, nudging until he was balanced on his wobbly hands, pins and needles shooting through his fingers. One of Dean’s hands was braced down beside his, but the other was wrapped around his shoulders, tight, just below Sam’s neck.

Sam didn’t know if it was the way the angle had changed or the faint threat of violence in that strong forearm bumping against his throat, but some switch flipped low in his belly, and he felt like he was unspooling rapidly. Every thrust drove a sharp cry out of his chest and he didn’t even notice that he was suddenly holding up their combined weight, Dean’s other hand now snaking along his belly and between his legs. The pressure against his mound might have even been enough on its own, but the rough, calloused pad of one of Dean’s fingers found its way in against the hood of his clit and Sam wailed—honest to God wailed—as the force of Dean’s hips rocked him against Dean’s hand over and over again. Dean might have come behind him but Sam couldn’t really hear anything over the blood pounding in his ears. The rocking didn’t stop and Dean’s breath was hot on his neck, and it was only a few more seconds of agony before an orgasm shook through Sam and knocked him trembling down onto his forearms, whimpering and weak.

It was a full minute before Sam could see or hear worth anything again, before he realized Dean had gone still against him, now holding up his own weight and stroking over Sam’s skin soothingly. He was mumbling nonsense again, praise and comfort and _Sammy,_ always _Sammy,_ like a prayer, and Sam let himself sink down slowly against the mattress, sore and spent. Dean collapsed down beside him, and Sam was pretty sure he heard the wet sound of a condom being tied off, but he didn’t want to look.

“Trust you,” he mumbled fondly.

The light snapped off and Dean settled in behind him to be the big spoon, pulling the blanket up over the both of them. “Good girl,” he said, nosing into Sam’s hair, and Sam smiled in the safety of the dark. “Good girl.”

**Author's Note:**

> PSA: There are guys out there in the world who will eat that pussy until their jaws give out, and they are precious treasures. Just remember, if you find one, to keep an eye on your skin/pH health. Not everyone's body is prepared for _quite_ that much friction or saliva over an extended period.


End file.
